Harrison told the AP she would change her identity from “female” to “TransWoman.”

“All too often transgender people like myself and other gender nonconforming people are given this binary option, do you want to be male or female? What is your gender? And it's kind of disheartening because none of those let us tell others who we really are," she told the AP.

Facebook users can choose a private setting for gender identity too.

In a 2011 report, the Williams Institute estimated there are about 9 million people in the United States who identify themselves as lesbian, gay, bisexual, or transgender, with about 700,000 who are transgender.

A petition on Change.org about two years ago was started to ask Facebook founder Mark Zuckerberg to add a gender neutral option, and it got 695 votes before being closed. http://www.change.org/petitions/facebook-add-a-gender-neutral-option-in-facebook-s-account-settings

The Facebook software change that allows the new gender options includes letting users select pronouns that will be used to refer to themselves, such as he, she, or they.

Not all thought the changes were necessary.

"Those petitioning for the change insist that there are an infinite number of genders, but just saying it doesn't make it so,” Jeff Johnston, with Focus on the Family, told the AP. “That said, we have a great deal of compassion for those who reject their biological sex and believe they are the opposite sex."